Carbapenems are a clinically important antibiotic family. More than 50 naturally occurring carbapenam/ems are known and are distinguished primarily by their C-2/C-6 side chains where many are only differentiated by the oxidation states of these substituents. With a limited palette of variations, the carbapenem family comprises a natural combinatorial library and C-2/C-6 oxidation is associated with increased efficacy.
The (8R)-hydroxyl group historically is a troublesome feature of synthetic routes to clinically-used carbapenem β-lactam antibiotics. Unlike other commonly-used members of this antibiotic family (e.g., penicillins, cephalosporins, and clavulanic acid), which are wholly or partially fermentation products, carbapenems are produced commercially by entirely synthetic means and, as a consequence, are expensive to produce.